July 8, 2022

For immediate release

Contact: Myrna Hayes, President, Mare Island Heritage Trust
Former Founding Volunteer Preserve Manager, 2007-2019
CELL PH: 707-249-9633
EMail: myrnahayes@mac.com

105th Anniversary Remembrance at the Mare Island Shoreline Heritage Preserve
Free guided history tours of the gravesites and locations where the WWI explosion took place that killed the
Mare Island Naval Magazine Chief Gunner and his family and employees, Saturday and Sunday, July 9 and 10, 2022 3:00-4:00pm

[VALLEJO], CA – Saturday, July 9, 2022 and Sunday, July 10, 2022, 3:00pm-4:00pm, the Mare Island Heritage Trust will host a 105th Anniversary Remembrance at the Mare Island Shoreline Heritage Preserve to mark the 105th anniversary of an explosion at the Mare Island Naval Magazine (Ammunition Depot) determined by the US Navy to be the work of an enemy agent at the beginning of WWI. Now, 105 years after the explosion killed Chief Gunner Allan S. MacKenzie and his wife and 2 youngest daughters, along with 2 civilian employees, new evidence points to the cause as a murder-suicide. The case for this new conclusion is made in an article by Historian and Author Stephen C. Ruder, published in the June 2022 issue of the Naval History Magazine, a publication of the U.S. Naval History Institute. https://www.usni.org/magazines/naval-history-magazine/2022/june/who-really-blew-mare-island

Saturday, July 9, 2022 is the 105th anniversary of an explosion that rocked the US Navy and its’ naval base at Mare Island and killed 6 people, four of which were the Chief Gunner of the Mare Island Naval Ammunition Depot, Allen S. MacKenzie, his 39 year old wife Malvina and their two youngest daughters, Dorothy, age 12 and Mildred, ‘Millie”, age 8. The additional two deaths were the Ammunition Depot Gardener and the longest serving employee of the Ammunition Depot. Join Myrna Hayes, founding manager of the Mare Island Shoreline Heritage Preserve from 2007-2019 and President of the Mare Island Heritage Trust Saturday, July 9 and Sunday, July 10 for a presentation and a guided tour of the explosion site, the location of the home in which the family was killed and a walk to the Mare Island Naval Cemetery to visit the graves of the MacKenzie family. The public may consider bringing flowers to place at the gravesite in remembrance of the family. The guided tour begins at 3:00pm at the former visitor center parking lot 167 O’Hara Ct. and will be from one half hour to 45 minutes in length. The Mare Island Shoreline Heritage Preserve is located at the southernmost end of Azuar Dr. on Mare Island in Vallejo, CA. Meet Myrna Hayes at the parking lot. Call/text her with questions and for directions. phone: 707-249-9633. email: myrnahayes@mac.com The Mare Island Shoreline Heritage Preserve is open Friday, Saturday, Sunday, 8:00am-5:00pm.

Myrna Hayes has written an e-book (Link to the e-book is on the Mare Island Preserve website: mareislandpreserve.com) about the MacKenzie family and the explosion that occurred July 9, 1917 with personal information about the family, excerpts from investigation reports and references to newspaper articles, excerpts from the Cemetery book by Peggy O’Drain and Joyce Giles of the Mare Island Historic Park Foundation and a link to the June 2022 publication of an article by Stephen C. Ruder in the Naval History Magazine in which he provides a convincing argument for an alternative cause of the explosion from the one the US Navy reached a conclusion of in 1917 and up until now. Note: This link is only available without the PayWall until July 22, 2022. https://www.usni.org/magazines/naval-history-magazine/2022/june/who-really-blew-mare-island

The explosion killed the Chief Gunner of the Mare Island Naval Magazine, Allen MacKenzie and his wife Malvina, along with their two youngest daughters, Dorothy, age 12 and Mildred, age 8. Their oldest daughter Roberta, age 18 was in Ohio at the time, preparing for her marriage. Two other employees of the Naval Magazine were killed that day and 31 injured. Navy investigators concluded that the explosion which occurred just before 8:00am the morning of July 9 was an act of sabotage by an enemy agent attached to the German Consulate in San Francisco. The explosion of black powder stored in a magazine close by to the family’s residence and across the road from the entrance to the Preserve’s current visitor center, was felt as an earthquake as far away as Santa Rosa, CA, 50 miles away. It rocked the town of Vallejo, blowing out windows and doors of the Southern Pacific Railroad vessel, the El Capitan and injuring workers aboard the vessel. New information challenges that assumption. In a June 2022 publication of an article by Stephen C. Ruder in the Naval History Magazine, he provides a convincing argument for an alternative cause of the explosion from the one the US Navy reached a conclusion of in 1917 and up until now. Note: This link is only available without the PayWall until July 22, 2022. https://www.usni.org/magazines/naval-history-magazine/2022/june/who-really-blew-mare-island

The 105th Anniversary Remembrance will include a brief commemorative service at approximately 3:30pm with the laying of a wreath at the gravesites of the MacKenzies in the Mare Island Naval Cemetery at the end of guided walking tours scheduled Saturday and Sunday, July 9 and 10, 2022, 3:00pm-4:00pm conducted by Myrna Hayes, President, Mare Island Heritage Trust. Myrna Hayes, the founding former volunteer Preserve Manager, 2007-2019, will give a brief presentation beginning at 3:00pm each day, followed immediately by a tour of the explosion site, the home location, and the gravesites in the Naval Cemetery. To give the public a modern-day sense of the setting and afford a place of quiet contemplation, those who join the tour will first walk up a gentle slope behind the currently closed visitor center on the hillside in the approximate location of the family’s home. Members of the public are invited to bring flowers and even toys and note cards or other items of remembrance to place at the gravesites.
The July 9, 1917 explosion remembered on the 105th anniversary, is one of three explosions that occurred at the Mare Island Naval Ammunition Depot in the months of June and July. June 13, 2022, was the 130th anniversary of an explosion that killed 15 crew of the USS Boston. On the 125th anniversary of that explosion, Mayor Bob Sampayan and the Vallejo City Council issued a proclamation that also recognized the July 9, 1917 explosion that killed Chief Gunner MacKenzie and his wife and two youngest daughters, along with two employees.

“In some ways it is quite a personal burden to focus my attention on planning this event in which we reflect on this third explosion in a series that occurred at the Mare Island Naval Ammunition Depot over the span of 25 years from the 1892 explosion that killed 15 crew of the USS Boston, to the 1901 explosion of 300 tons of black powder, to the 1917 explosion that killed the MacKenzie family. I am awed that we are still so deeply moved by the remembrance of something that occurred so long ago and yet, continues to touch us so deeply. It is in our humanness, our very nature, that our soul and heart are capable of reaching across generations to tragic moments in time to still feel the loss and share the grief of a family, a community and a nation”, reflects Myrna Hayes, the volunteer Preserve Manager.
In fact, Myrna Hayes credits a host of inspiring aspects of this story, for her continued interest in this story. First, is the connection she has maintained with the descendants of the MacKenzie family and secondly, the inspiration of the recent publishing of the long-awaited article in the Navy History Magazine, both of which led her to prepare the e-book that is attached. It is a personal account of her involvement in this moment in our nation’s military history on what she considers sacred grounds of the native peoples of the region and one of the reasons she co-founded and managed the lands on which the explosion occurred. After serving on a Mayoral appointed Taskforce for the City of Vallejo for 4 years and having a hand in the finalization of the final Report, she orchestrated the opening of the wildlands parklands to the public for the first time in 150 years with a number of commemorative and exploratory events, in 2007. She then, went on to co-found the Mare Island Shoreline Heritage Preserve on a permanent basis in April 2008. She and her nonprofit organization, the Mare Island Heritage Trust, were abruptly and without being given a reason, dismissed as the founders, funders and operating managers of the Preserve in late September 2019. Rallying the “wildlands community” that had been established and flourished under her leadership, the online petition requesting that the nonprofit land trust be returned as the managers, which volunteers created in Fall of 2019, is as of July 8, 2022, closing in on the 10,000 signature goal with just 52 more signatures needed to reach that goal. The petition can be found on the mareislandpreserve.com website. 

Excerpts from the Navy investigation archived in the National Archives, Washington D.C. Many of the referenced photos are included in the e-book by Myrna Hayes.

Source: Mare Island Naval Shipyard letter dated 14 July 1917 from Public Works Officer to Commandant

Subject: Report showing condition of buildings at the Naval Ammunition Depot following explosion on July 9, 1917

“The black powder magazine, Building 40, was a brick building, 30’ wide and 80’ long, 1 story high with wooden floor joists and wooden floor with ventilated air space underneath. A piece of the iron framing (of the roof trusses) fell on the Naval Hospital building and penetrated through the roof and two floors.”

“Looking west. Building 57 was a one-story double quarters frame construction, erected in 1913. The south half of the building was occupied by Chief Gunner A.S. McKenzie and family, who were all killed.”

Photo No. 3 (showing debris in foreground) “Picture taken at Building 32, looking west. In the right foreground, showing earthwork thrown up at site of Building 40; in the center, showing debris of double quarters Building 57.” (Note the two persons standing in the crater of Bldg 40 and the probable Marines on guard in the enclosure on the left of the photograph.)  File titled MINSY b57 b40

Photo No. 5 (showing crater and wrecked building in background) “Looking east from point in front of Building 57, showing crater of Building 40 and Building 54, magazine. The center is the wreckage of Building 32.  File titled MISNY B40 Crater

Original file located at National Archives WDC: 
71 10W3 21 29 6
E12 General Correspondence Box 40 

The enclosed map extract in the e-book was found in:

Source:  Record of Proceedings of a Board of Investigation convened at The Navy Yard, Mare Island, California by order of the Commandant, Navy Yard and Station, to inquire into and report upon THE EXPLOSION OF THE BLACK POWDER MAGAZINE AT THE NAVAL AMMUNITION DEPOT, MARE ISLAND, CALIF., AT OR ABOUT 7:55 A.M. JULY 9, 1917 dated  July 10, 1917

Located at National Archives WDC

125  11W2  22   11   2

E30   Proceedings of Courts of Inquiry   Box 98  Case 7038

Excerpt from A Developmental History of Mare Island Chapter 3, Flynn and Roop

1917, JULY 9 Explosion at the powder magazines. 2,000 tons of black powder
exploded as one charge. 13 buildings were destroyed, several others damaged, Thirty
one persons injured, and six killed. This explosion destroyed both storehouses and
residential structures (Lott 1954). The rebuilding program that followed probably
resulted in the final burial or destruction of Sol-232, the prehistoric Indian site found by
Nelson in 1907.
1917, SEPTEMBER 25 Board of investigation examining causes of the magazine
explosion of July 7 reports that the damage was due to “the deliberate act of a person or
persons unknown.” It was later confirmed that the explosion was an act of sabotage
performed by Lieutenant William Van Brincken, a military attaché at the German
consulate in San Francisco (Lott 1954:171).

Excerpt from MARE ISLAND CEMETERY 1856 -1921 VOLUME I, pages 24-25

Compiled by:
Peggy O’Drain, MIHPF(Mare Island Historic Park Foundation) and Joyce Giles, MIHPF

Digitally formatted by:
Tony W. Liang

On July 9, 1917, Mrs. MacKenzie was preparing to go to Cleveland to join an older daughter, Roberta, for her marriage to James Osborn. She left two weeks prior to make preparations. She planned to leave at 12:30 for the first part of the journey. However, there was an explosion which wrecked the black powder magazine at 7:56 am. The officer’s duplex quarters were completely demolished, and the MacKenzie family was thrown out of the house onto the hillside, dying instantly. People walking in the direction of the magazine saw a flash of flame. The smoke poured out, and the entire building where the black powder was stored rose in the air. Smoke cleared, and you could see wreckage. Thirteen buildings, including packing houses, shell houses, etc., were partially demolished. The adjacent house was occupied by Gunner and Mrs. McKenna, their baby and the baby’s nurse. However, the adjacent duplex was not destroyed, and the family survived. 31 people were injured by the explosion, some seriously. Neil C. Damstedt, who opened all the magazine buildings in the morning to take the temperatures, was also killed. His body was mangled. He had been employed at the magazine for 24 years, and a long-time Vallejoan. Damstedt left a wife and four children. Neil Damstedt was a Mason, and his funeral was handled by the Solano Lodge of Masons, and he was interred at the Masonic and Odd Fellows Cemetery.
The other person killed by the explosion was George Stanton of South Vallejo. He was the gardener at the magazine, and his body was found near the MacKenzie’s. His funeral was at 8pm, and the body shipped to Oakland for cremation. Stanton was 75, and a native of England. He left a wife, daughter and 3 grandchildren. Fire bells immediately sounded, as all rushed to the scene. All Naval doctors living in Vallejo were rushed to Mare Island Hospital. Clergymen were also summoned. Marines came to surround and guard the area all day. No one was allowed to leave the Yard. The thought was that the Germans caused the explosion. Stores and homes in Vallejo were damaged by the explosion. Many store windows in downtown Vallejo were shattered. South Vallejo also suffered structural damage to buildings. People soon learned that their insurance did not cover this damage to windows. Two bricks were thrown across the channel and struck in the Sperry Mill property without causing damage. Windows were also broken in Crockett, and shock waves were felt in other cities within a 50-mile radius. Telephone and telegraph offices were crowded as people were calling family to announce they were safe. 823 messages were handled by the telegraph office. There were many thoughts and theories of what caused the explosion. Marines continued to guard the magazine, with orders to shoot-to-kill anyone there after dark. Civilians living in area of magazine now had to live off the shipyard, and Marines would open and close the magazines.
A board of inquiry tried to determine the cause of the explosion, but most evidence was destroyed in the explosion. On September 25, an announcement stated that the disaster was “the deliberate act of a person or persons unknown”. Two days before there had been a fire at the stables, and 12 out of 50 horses were killed. A month later, a report came that a local dance hall had a bomb, and it was immediately cleared. Vallejo became very “bomb conscious”. Proof of a German sabotage plot involving a military attaché in San Francisco was revealed at the end of World War I.
Source: Vallejo Evening Chronicle, July 9, 11, 17 of 1917
Public access at the Preserve

Key features of the Preserve are spectacular scenic vistas encompassing 7 Bay Area counties, Mt. Diablo, Mt. Tamalpais and Mt. St. Helena, the Carquinez Strait and Sonoma and Napa Valleys and the U.S. Navy’s first cemetery in the Pacific, founded in 1858. The Preserve is located at the southern end of Azuar Dr.. at 167 O’Hara Court on Mare Island in Vallejo, CA.

The first parcels of the Preserve, were transferred to the City of Vallejo in a grant from the legislature through the California State Lands Commission in 2002 for public trust uses such as a park, for all Californians. Additional parcels were transferred in the Fall of 2010. The remainder of the 215-acre site is still undergoing environmental cleanup by the U.S. Navy.

Directions: The route is simple but confusing sometimes if using standard navigation systems. The best route is described below:

From Hwy 80 West and Eastbound: Exit Tennessee St./ Mare Island. Continue on Tennessee St. across the Wichels Causeway (blue bridge) to the deadend bypassing Railroad Ave. to Azuar Dr. Turn left 2.5 miles continuing past a traffic circle at Sundance Dr., past Touro University, past the US Army Reserve, through a gate which will be fully swung open to parking at the Visitor Center at 167 O’Hara Ct. The Naval Cemetery is one quarter mile beyond the Trailhead.

Please note: Historic and current photos are available. Tours of The Preserve are available to any reporter or photographer covering these events. Call Myrna Hayes, 707-249-9633 (cell) to schedule. Photo credits: MacKenzie family descendants